Studies on the subcellular loci of a specific hepatic membrane protein responsible for the recognition and catabolism of desialylated serum glyco-proteins have established the presence of this receptor on the internal (luminal) surface of the golgi complex and the smooth membranes in contrast to its location on the external (cytosolic) surface of the lysosomes. The latter finding has been correlated with the survival of this receptor under conditions of maximal catabolism of the receptor-asialoglycoprotein complex. Further insight into the mechanism of this translocation of the membrane protein has been obtained in a model system utilizing the rapid pinocytosis of latex particles by isolated hepatocytes.